1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2008 Isilon Inc http://www.isilon.com/
5 * Authors: Doug Rabson <dfr@rabson.org>
6 * Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org>
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD$");
32
33#include <sys/param.h>
34#include <sys/kernel.h>
35#include <sys/kobj.h>
36#include <sys/lock.h>
37#include <sys/malloc.h>
38#include <sys/module.h>
39#include <sys/mutex.h>
40#include <sys/priv.h>
41#include <sys/syscall.h>
42#include <sys/sysent.h>
43#include <sys/sysproto.h>
44
45#include <kgssapi/gssapi.h>
46#include <kgssapi/gssapi_impl.h>
47#include <rpc/rpc.h>
48#include <rpc/rpc_com.h>
49#include <rpc/rpcsec_gss.h>
50
51#include "gssd.h"
52#include "kgss_if.h"
53
54MALLOC_DEFINE(M_GSSAPI, "GSS-API", "GSS-API");
55
56/*
57 * Syscall hooks
58 */
59static struct syscall_helper_data gssd_syscalls[] = {
60	SYSCALL_INIT_HELPER(gssd_syscall),
61	SYSCALL_INIT_LAST
62};
63
64struct kgss_mech_list kgss_mechs;
65CLIENT *kgss_gssd_handle;
66struct mtx kgss_gssd_lock;
67
68static int
69kgss_load(void)
70{
71	int error;
72
73	LIST_INIT(&kgss_mechs);
74	error = syscall_helper_register(gssd_syscalls, SY_THR_STATIC_KLD);
75	if (error != 0)
76		return (error);
77	return (0);
78}
79
80static void
81kgss_unload(void)
82{
83
84	syscall_helper_unregister(gssd_syscalls);
85}
86
87int
88sys_gssd_syscall(struct thread *td, struct gssd_syscall_args *uap)
89{
90        struct sockaddr_un sun;
91        struct netconfig *nconf;
92	char path[MAXPATHLEN];
93	int error;
94	CLIENT *cl, *oldcl;
95
96	error = priv_check(td, PRIV_NFS_DAEMON);
97	if (error)
98		return (error);
99
100	error = copyinstr(uap->path, path, sizeof(path), NULL);
101	if (error)
102		return (error);
103	if (strlen(path) + 1 > sizeof(sun.sun_path))
104		return (EINVAL);
105
106	if (path[0] != '\0') {
107		sun.sun_family = AF_LOCAL;
108		strlcpy(sun.sun_path, path, sizeof(sun.sun_path));
109		sun.sun_len = SUN_LEN(&sun);
110
111		nconf = getnetconfigent("local");
112		cl = clnt_reconnect_create(nconf,
113		    (struct sockaddr *) &sun, GSSD, GSSDVERS,
114		    RPC_MAXDATASIZE, RPC_MAXDATASIZE);
115		/*
116		 * The number of retries defaults to INT_MAX, which effectively
117		 * means an infinite, uninterruptable loop.  Limiting it to
118		 * five retries keeps it from running forever.
119		 */
120		if (cl != NULL) {
121			int retry_count = 5;
122			CLNT_CONTROL(cl, CLSET_RETRIES, &retry_count);
123		}
124	} else
125		cl = NULL;
126
127	mtx_lock(&kgss_gssd_lock);
128	oldcl = kgss_gssd_handle;
129	kgss_gssd_handle = cl;
130	mtx_unlock(&kgss_gssd_lock);
131
132	if (oldcl != NULL) {
133		CLNT_CLOSE(oldcl);
134		CLNT_RELEASE(oldcl);
135	}
136
137	return (0);
138}
139
140int
141kgss_oid_equal(const gss_OID oid1, const gss_OID oid2)
142{
143
144	if (oid1 == oid2)
145		return (1);
146	if (!oid1 || !oid2)
147		return (0);
148	if (oid1->length != oid2->length)
149		return (0);
150	if (memcmp(oid1->elements, oid2->elements, oid1->length))
151		return (0);
152	return (1);
153}
154
155void
156kgss_install_mech(gss_OID mech_type, const char *name, struct kobj_class *cls)
157{
158	struct kgss_mech *km;
159
160	km = malloc(sizeof(struct kgss_mech), M_GSSAPI, M_WAITOK);
161	km->km_mech_type = mech_type;
162	km->km_mech_name = name;
163	km->km_class = cls;
164	LIST_INSERT_HEAD(&kgss_mechs, km, km_link);
165}
166
167void
168kgss_uninstall_mech(gss_OID mech_type)
169{
170	struct kgss_mech *km;
171
172	LIST_FOREACH(km, &kgss_mechs, km_link) {
173		if (kgss_oid_equal(km->km_mech_type, mech_type)) {
174			LIST_REMOVE(km, km_link);
175			free(km, M_GSSAPI);
176			return;
177		}
178	}
179}
180
181gss_OID
182kgss_find_mech_by_name(const char *name)
183{
184	struct kgss_mech *km;
185
186	LIST_FOREACH(km, &kgss_mechs, km_link) {
187		if (!strcmp(km->km_mech_name, name)) {
188			return (km->km_mech_type);
189		}
190	}
191	return (GSS_C_NO_OID);
192}
193
194const char *
195kgss_find_mech_by_oid(const gss_OID oid)
196{
197	struct kgss_mech *km;
198
199	LIST_FOREACH(km, &kgss_mechs, km_link) {
200		if (kgss_oid_equal(km->km_mech_type, oid)) {
201			return (km->km_mech_name);
202		}
203	}
204	return (NULL);
205}
206
207gss_ctx_id_t
208kgss_create_context(gss_OID mech_type)
209{
210	struct kgss_mech *km;
211	gss_ctx_id_t ctx;
212
213	LIST_FOREACH(km, &kgss_mechs, km_link) {
214		if (kgss_oid_equal(km->km_mech_type, mech_type))
215			break;
216	}
217	if (!km)
218		return (NULL);
219
220	ctx = (gss_ctx_id_t) kobj_create(km->km_class, M_GSSAPI, M_WAITOK);
221	KGSS_INIT(ctx);
222
223	return (ctx);
224}
225
226void
227kgss_delete_context(gss_ctx_id_t ctx, gss_buffer_t output_token)
228{
229
230	KGSS_DELETE(ctx, output_token);
231	kobj_delete((kobj_t) ctx, M_GSSAPI);
232}
233
234OM_uint32
235kgss_transfer_context(gss_ctx_id_t ctx)
236{
237	struct export_sec_context_res res;
238	struct export_sec_context_args args;
239	enum clnt_stat stat;
240	OM_uint32 maj_stat;
241
242	if (!kgss_gssd_handle)
243		return (GSS_S_FAILURE);
244
245	args.ctx = ctx->handle;
246	bzero(&res, sizeof(res));
247	stat = gssd_export_sec_context_1(&args, &res, kgss_gssd_handle);
248	if (stat != RPC_SUCCESS) {
249		return (GSS_S_FAILURE);
250	}
251
252	maj_stat = KGSS_IMPORT(ctx, res.format, &res.interprocess_token);
253	ctx->handle = 0;
254
255	xdr_free((xdrproc_t) xdr_export_sec_context_res, &res);
256
257	return (maj_stat);
258}
259
260void
261kgss_copy_buffer(const gss_buffer_t from, gss_buffer_t to)
262{
263	to->length = from->length;
264	if (from->length) {
265		to->value = malloc(from->length, M_GSSAPI, M_WAITOK);
266		bcopy(from->value, to->value, from->length);
267	} else {
268		to->value = NULL;
269	}
270}
271
272/*
273 * Acquire the kgss_gssd_handle and return it with a reference count,
274 * if it is available.
275 */
276CLIENT *
277kgss_gssd_client(void)
278{
279	CLIENT *cl;
280
281	mtx_lock(&kgss_gssd_lock);
282	cl = kgss_gssd_handle;
283	if (cl != NULL)
284		CLNT_ACQUIRE(cl);
285	mtx_unlock(&kgss_gssd_lock);
286	return (cl);
287}
288
289/*
290 * Kernel module glue
291 */
292static int
293kgssapi_modevent(module_t mod, int type, void *data)
294{
295	int error = 0;
296
297	switch (type) {
298	case MOD_LOAD:
299		rpc_gss_entries.rpc_gss_refresh_auth = rpc_gss_refresh_auth;
300		rpc_gss_entries.rpc_gss_secfind = rpc_gss_secfind;
301		rpc_gss_entries.rpc_gss_secpurge = rpc_gss_secpurge;
302		rpc_gss_entries.rpc_gss_seccreate = rpc_gss_seccreate;
303		rpc_gss_entries.rpc_gss_set_defaults = rpc_gss_set_defaults;
304		rpc_gss_entries.rpc_gss_max_data_length =
305		    rpc_gss_max_data_length;
306		rpc_gss_entries.rpc_gss_get_error = rpc_gss_get_error;
307		rpc_gss_entries.rpc_gss_mech_to_oid = rpc_gss_mech_to_oid;
308		rpc_gss_entries.rpc_gss_oid_to_mech = rpc_gss_oid_to_mech;
309		rpc_gss_entries.rpc_gss_qop_to_num = rpc_gss_qop_to_num;
310		rpc_gss_entries.rpc_gss_get_mechanisms = rpc_gss_get_mechanisms;
311		rpc_gss_entries.rpc_gss_get_versions = rpc_gss_get_versions;
312		rpc_gss_entries.rpc_gss_is_installed = rpc_gss_is_installed;
313		rpc_gss_entries.rpc_gss_set_svc_name = rpc_gss_set_svc_name;
314		rpc_gss_entries.rpc_gss_clear_svc_name = rpc_gss_clear_svc_name;
315		rpc_gss_entries.rpc_gss_getcred = rpc_gss_getcred;
316		rpc_gss_entries.rpc_gss_set_callback = rpc_gss_set_callback;
317		rpc_gss_entries.rpc_gss_clear_callback = rpc_gss_clear_callback;
318		rpc_gss_entries.rpc_gss_get_principal_name =
319		    rpc_gss_get_principal_name;
320		rpc_gss_entries.rpc_gss_svc_max_data_length =
321		    rpc_gss_svc_max_data_length;
322		mtx_init(&kgss_gssd_lock, "kgss_gssd_lock", NULL, MTX_DEF);
323		error = kgss_load();
324		break;
325	case MOD_UNLOAD:
326		kgss_unload();
327		mtx_destroy(&kgss_gssd_lock);
328		/*
329		 * Unloading of the kgssapi module is not currently supported.
330		 * If somebody wants this, we would need to keep track of
331		 * currently executing threads and make sure the count is 0.
332		 */
333		/* FALLTHROUGH */
334	default:
335		error = EOPNOTSUPP;
336	}
337	return (error);
338}
339static moduledata_t kgssapi_mod = {
340	"kgssapi",
341	kgssapi_modevent,
342	NULL,
343};
344DECLARE_MODULE(kgssapi, kgssapi_mod, SI_SUB_VFS, SI_ORDER_ANY);
345MODULE_DEPEND(kgssapi, xdr, 1, 1, 1);
346MODULE_DEPEND(kgssapi, krpc, 1, 1, 1);
347MODULE_VERSION(kgssapi, 1);
348